心脏电生理及射频消融基础-(2).ppt

电生理相关资料Cardiac vein stenosisPTCA with 3.5 mm balloonFinal resultModified Seldinger technique for percutaneous catheter sheath introductionSequence of P Wave GenerationSinusNodeSAJunctionAtrium(P wave)Non-visible process on the EKGAV node“Slowzone”IVCLeadIISUMMARYMechanisms of SVTAtrial TachycardiaAVNRTAVRTFPSPDifferential Diagnosis of NCTn nShort RPShort RPn nAVRTAVRTn nATATn nSlow-SlowSlow-SlowAVNRTAVNRTn nLong RPLong RPn nATATn nAtypicalAtypicalAVNRTAVNRTn nPJRTPJRTn nP buried in QRSP buried in QRSn nTypicalAVNRTTypicalAVNRTn nATATn nJETJETSUMMARYn nObtain a 12 lead ECG.The location of the P wave will dictate Obtain a 12 lead ECG.The location of the P wave will dictate the differential diagnosisthe differential diagnosisn nIf hemodynamically unstable(chest pain,heart failure,If hemodynamically unstable(chest pain,heart failure,hypotension)-CARDIOVERSIONhypotension)-CARDIOVERSIONn nIf hemodynamically stable-AV NODAL AGENTIf hemodynamically stable-AV NODAL AGENTn nLong term therapy depends on mechanism and can be Long term therapy depends on mechanism and can be conservative,pharmacologic or invasive conservative,pharmacologic or invasive n nEP study often needed for definitive characterization of EP study often needed for definitive characterization of mechanism and can cure most SVTs with 90%success ratemechanism and can cure most SVTs with 90%success rateAVNRTAtrial flutter sawtooth or picket fenceAtrial flutter with rapid responseArrhythmias:SA BlockPQRS TArrhythmias:Atrial FlutterSteps to reading ECGsn nWhat is the rate?Both atrial and ventricular if they What is the rate?Both atrial and ventricular if they are not the same.are not the same.n nIs the rhythm regular or irregular?Is the rhythm regular or irregular?n nDo the P waves all look the same?Is there a P wave Do the P waves all look the same?Is there a P wave for every QRS and conversely a QRS for every P for every QRS and conversely a QRS for every P wave?wave?n nAre all the complexes within normal time limits?Are all the complexes within normal time limits?n nName the rhythm and any abnormalities.Name the rhythm and any abnormalities.Raten nLook at complexes in a 6-second strip and count the complexes;that will give you a rough estimate of raten nCount the number of large boxes between two complexes and divide into 300 n nCount the number of small boxes between two complexes and divide into 1500 n nEstimate rate by sequence of numbers(see next slide)Bundle branch blocksLook at the QRS morphology in V1 and V6AVNRTn nAcute treatmentAcute treatment ATP or Verapamil ATP or Verapamil Cardioversion if BP Cardioversion if BP n nLong termLong term Drugs,verapamil or b-Drugs,verapamil or b-blockerblocker EPS and RFA EPS and RFAAVRTn nWPW or concealed WPW or concealed accessory pathwayaccessory pathwayn nacute and chronic acute and chronic treatment similar to treatment similar to AVNRTAVNRTn navoid b-blocker and avoid b-blocker and verapamil in known verapamil in known WPWWPWAtrial Fluttern nMarcoreentrant circuit Marcoreentrant circuit in RAin RAn nterminate by terminate by cardioversion with high cardioversion with high success ratesuccess raten npoorly controlled by poorly controlled by medical therapymedical therapyn nEPS+RFAEPS+RFA“Typicalisthmusdependentatrialflutter”isduetoamacroreentrantcircuitaroundthetricuspidvalveThisrhythmcanbestoppedbypacingandcuredwithablationEmbolicriskmaybelessthaninfibrillation,butsamerecommendationsapplyElectrophysiologyIISupraventricularArrhythmiasAtrialFlutterVentricularrate150bpm“Sawtooth”pwavesAtrialFlutterElectrophysiologyIISupraventricularArrhythmiasAtrioventricularNodalReentrantTachycardia(AVNodeReentryorAVNRT)MostcommoncauseofparoxysmalSVTintheyoungadultOccursoverasmallreentrantcircuitlocatedneartheAVnodeThecircuitconsistsofafastandslowpathwayconnectedbyacommontopandbottompathwayElectrophysiologyIISupraventricularArrhythmiasAVNodeReentryTachycardiaRateof145bpm(ShortRPtachycardia)ElectrophysiologyIISupraventricularArrhythmiasRetrogradepwavesRP=60msecEctopicAtrialTachycardia(LongRPtachycardia)UncommoncauseofparoxysmalSVTintheyoungadult(0.09sPR0.09sn n预激波额面电轴右偏预激波额面电轴右偏预激波额面电轴右偏预激波额面电轴右偏（9090120120度）度）度）度）右侧房室旁路的定位标准右侧房室旁路的定位标准n nV1V1导联导联导联导联QRSQRS波主波方向波主波方向波主波方向波主波方向向下（多呈向下（多呈向下（多呈向下（多呈rSrS型）型）型）型）n nV1V1导联导联导联导联P P波和波和波和波和QRSQRS波融波融波融波融合，二者间无等电位线，合，二者间无等电位线，合，二者间无等电位线，合，二者间无等电位线，PR0.07sPR0.07sn n预激波额面电轴左偏预激波额面电轴左偏预激波额面电轴左偏预激波额面电轴左偏（30306060度）度）度）度）n n右后、右右后、右侧游离壁：游离壁：、aVL、V5、V6导联预激波正向，激波正向，、aVF导联预激波激波负向或正向或正负双向。双向。n n右前游离壁：右前游离壁：、aVF导联预激波正向或正激波正向或正负双向。双向。前间隔房室旁路的定位标准前间隔房室旁路的定位标准n nV1V1导联导联导联导联QRSQRS波主波方向波主波方向波主波方向波主波方向向下（多呈向下（多呈向下（多呈向下（多呈rSrS型）型）型）型）n nV1V1导联导联导联导联P P波和波和波和波和QRSQRS波融波融波融波融合，二者间无等电位线，合，二者间无等电位线，合，二者间无等电位线，合，二者间无等电位线，PR0.07sPR0.21wouldbeclassifiedasfirstdegreeblock.UsuallythisblockisaboveHisbundleSecond degree-somePwavesarenotfollowedbyQRS.Oftenhasaregularsequence,i.e.,2:1or3:2.ThefirstnumberisthenumberofPwavespresentandthesecondisthenumberofQRSs.Whatisthis?Mobitz I(Wenckebach)thePRprogressivelylengthenswithonePwaveforeveryQRSuntilabeatisdropped.UsuallytheblockisaboveHisbundle.ThisiscommonincoronarypatientsandiscausedbyincreasedvagaltoneandusuallyeventuallydisappearswithnoproblemsMobitz IIthePRisconstantbutwithoccasionaldroppedbeats.ThisisamoreseriousarrhythmiabecausetheinjuryisprobablyinfastconductingtissuebelowtheHisbundlewhichisnotundervagalcontrol.ThisisunambiguouslyMobitzIIItisadangerousarrhythmiabecausetheheartmaysuddenlystartbeatingveryslowlyorevenstop.Complete heart block.SincethereisnoconductiondowntheAVnodepathwayatriaandventriclesbeatregularlybutatdifferentrates.SlowventricularrateUsuallytreatedwithpacemakerMaybetemporaryorintermittent.CanbeinducedbydrugsthatcauseincreasedvagotoniaWPW:Normallyconductingcardiacmusclebridgesthegapbetweenatriaandventricles.TheaccessorypathwayactivatestheventriclebeforenormalactivationviatheAVnode.ThePRintervalis100b/min1.NormalPwaves2.NormalorshortenedPRinterval3.QRSandTvectorsarenormal4.STsegmentsarenormal5.RRintervalshort15mm1500/100=15Fig3NormalsinusrhythmSinustachycardiaSinusbradycardiaSinusBradycardia25mm1500/60=25Premature ventricular contraction(PVC)1.Arisesfromectopicfocusinventricles2.EarlyQRSnotprecededbyaPwave(seefig4)3.WillhaveanunusualQRSshapea)oddvectorb)prolongedQRSdurationPremature ventricular contraction(PVC)1.Arisesfromectopicfocusinventricles2.EarlyQRSnotprecededbyaPwave(seefig4)3.WillhaveanunusualQRSshapea)oddvectorb)prolongedQRSduration4.AcompensatorypauseMultifocalPVCs.TwoseparatefociareoriginatingPVCsIrritableventricleIFallPVCareidenticalitisfromoneectopicsite(Unifocal).Premature atrial contraction(PAC)1.Arisesfromanectopicfocusintheatria.2.WillhaveanidentifiablePwavebuttheshapeofthePwavemaybealtered3.MayhaveanormalQRS4.MayhaveacompensatorypauseTheQRSmaybealteredifsomeoftheventricleisstillinitsrefractoryperiod.ThecompensatorypauseislackingbecausetheSAnodewasreset.Therhythmhasbeenshifted.Atrialfibrillation1.Irregularlyirregular2.NoPwavesTheAVnodekeepstheventricularratelowMaybetreatedwithdrugstodepressAVconductionandslowtheventricularrhythm:Betablockers,calciumchannelblockersCommon:willoccurinabout1/3ofthepopulationNotaseriousarrhythmiaunlessinWPWElectricalreentrycancausefibrillationsandtachycardias.Ventricular tachycardia(Fig9)1.Regularlyoccurringrhythmoriginatingfromaregularventricularectopicfocus.2.QRSmorphologyisusuallylikeaPVCBecause the cardiac output is very low it usually produces myocardial ischemia and often progresses to ventricular fibrillation Ventricular fibrillation(VF)1.Thought to be a reentrant excitation of the ventricles;premature impulse may arise during vulnerable period2.Irregular baseline with no identifiable waves3.No cardiac output.Usually the cause of sudden death4.May be the result of ischemia,lightning strike,electrocution,chest trauma,or drugs5.Requires CPR and electrical difibrillation.Patients do not spontaneously recover.ExtendedphasetwocauselongQTsyndrome.Q-Tintervalisrate-dependentandisanindexofthedurationofphase2intheventricularAP12x40=480ms12blocksLong QT syndrome1.Prolongeddurationofphase2causesanearlyafterdepolarization.Thatcantriggeranearlyactionpotentialcausingareentranttachycardia2.PatientsmayexperienceattacksofVTwithtorsades de pointes-awaxingandwaningoftheQRSmorphology(asifcirclingaroundapoint).3.LongQTisinducedbysomedrugsandcanbeduetogeneticabnormalitiesinsomepotassiumandcalciumchannels.Atpresent5separategeneticdefectshavebeenidentifiedwhichcauselongQT14 STEPS TO ASSURE A SUCCESSFUL READING AND UNDERSTANDING OF AN UNKNOWN ECG1.Istheventricularrhythmregular?2.AretherePwaves?3.Istheatrialrhythmregular?4.IsthereonePwaveforeachQRS?5.Whataretheatrialandventricularrates?6.WhatistheP-Rinterval?7.IstheP-Rintervalconstant?8.Arethereextraorprematurebeats?9.WhatistheQRSduration?10.DoestheQRSmorphologyindicatepresenceofaconductiondefect?11.WhatisthemeanelectricalQRSaxis?12.WhatisthemeanelectricalPwaveaxis?13.IsthereS-Tsegmentdeviation?14.AretherepathologicQwaves?Fig12asummaryofheartblocks.asummaryofotherarrhythmiasRARALALALVLVRVRVTypes of Supraventricular TachyarrhythmiasSinus Node ReentrySinus Node ReentryAtrial FlutterAtrial FlutterAutomatic Atrial TachycardiaAutomatic Atrial TachycardiaReentrant Atrial TachycardiaReentrant Atrial TachycardiaAtrioventricular NodalAtrioventricular NodalReentry(AVNRT)Reentry(AVNRT)AV Reentry via an AccessoryAV Reentry via an AccessoryAV Connection(AVRT)AV Connection(AVRT)Atrial Fibrillation(Not Shown)Atrial Fibrillation(Not Shown)Types of Paroxysmal Supraventricular TachycardiaAV NodalReentryAV ReciprocatingTachycardiaSinus Nodal ReentryIntra-atrial ReentryAutomatic AtrialTachycardiaMechanisms of Paroxysmal Supraventricular TachycardiasEnhanced Automaticity:Enhanced Automaticity:n nParoxysmal and AcuteParoxysmal and Acuten nChronicChronicRe-entry without Bypass Tracts:Re-entry without Bypass Tracts:n nAV Nodal Re-entry:Slow AV Nodal Re-entry:Slow Fast/Fast Fast/Fast Slow Slown nSinoatrial Nodal Re-entrySinoatrial Nodal Re-entryn nIntra-atrial Re-entryIntra-atrial Re-entryRe-entry in Association with Bypass Tracts:Re-entry in Association with Bypass Tracts:n nRe-entry with Anterograde AV Conduction(Orthodromic)Re-entry with Anterograde AV Conduction(Orthodromic)n nWith Evidence of Pre-excitation of 12-Lead ECGWith Evidence of Pre-excitation of 12-Lead ECGn nConcealed WPW(Bypass Tract Conducting only Retrogradely)Concealed WPW(Bypass Tract Conducting only Retrogradely)n nRe-entry with Anterograde Conduction Over Bypass tract(Antidromic)Re-entry with Anterograde Conduction Over Bypass tract(Antidromic)During TachycardiaDuring TachycardiaAccessory Pathways:Concealed Bypass Tract AV Reentrant TachycardiaAV NodeAV NodeBundle of HisBundle of HisLeft Bundle BranchLeft Bundle BranchP PRight Bundle BranchRight Bundle BranchConcealed BypassConcealed BypassTractTractElectrical Conduction in Atrial FlutterAV NodeAV NodeVentricular Rate 150-160(Most Often 2:1 AV Block)Ventricular Rate 150-160(Most Often 2:1 AV Block)ECG of FlutterECG of FlutterBaseline Coarsely or Finely Irregular;P Waves Absent.Baseline Coarsely or Finely Irregular;P Waves Absent.Ventricular Response(QRS)Irregular,Slow or RapidVentricular Response(QRS)Irregular,Slow or RapidCoarse FibrillationFine FibrillationAtrial FibrillationScheidt S,Erlebacher JA,Netter FH.Basic Electrocardiography ECG.Ciba-Geigy:First Printing,1986,p23.ElectrocardiogramAF is Associated WithCV DiseasesCV Diseasesn nCT surgeryCT surgeryn nValvular orValvular orcongential diseasecongential diseasen nHypertensionHypertensionn nCardiomyopathyCardiomyopathyn nHeart failureHeart failuren nMyocardial ischemia/MIMyocardial ischemia/MIn nPeri/myocarditisPeri/myocarditisn nInfiltrative heart diseaseInfiltrative heart diseasen nCardiac traumaCardiac traumaSystemic DiseasesSystemic Diseasesn nAgeAgen nDTs,sympathetic stormDTs,sympathetic stormn nElectrolyte disordersElectrolyte disordersn nThyrotoxicosisThyrotoxicosisn nFever/hypothermiaFever/hypothermian nHypovolemiaHypovolemian nDiabetesDiabetesn nAnemiaAnemian nPulmonary diseasePulmonary diseasen nCerebrovascular diseaseCerebrovascular diseaseAntiarrhythmic Drugs vs.Therapeutic GoalAtriumAtriumHis PurkinjeHis PurkinjeVentricleVentricleAPAPAV NodeAV NodeIbutilideIbutilideQuinidineQuinidineProcainamideProcainamideDisopyramideDisopyramideFlecainideFlecainidePropafenonePropafenoneSotalolSotalolAmiodaroneAmiodaroneVagal StimulationVagal StimulationDigoxinDigoxinb b b b-Blocking Drugs-Blocking DrugsVerapamilVerapamilDiltiazemDiltiazemAdenosineAdenosinen nAtrial flutter